New target mounted.

106Cd 1 mg/cm2

181Ta  1.2 mg/cm2

Problems in alignment. Offset of 100 um, in spite of the fact that a gap is visible at this distance, and a hair could be moved in between stopper and the target.
Decided to close and pump anyway, after several attempts to improve the alignment.

Stopper same as before, slightly more stretched.

/onlineNEDA_00/xData/hil099/run_0045_07-03-2023_09h14m17s/needleRU_i45_0045_0027.caendat

/onlineNEDA_00/xData/hil099/run_0045_07-03-2023_09h14m17s/needleLF_i44_0045_0010.adf

Since 2:32 increased counting rate observed:

Sinde 3:45 decrease to 1.5 kHz ch4.

run control = 48

/onlineNEDA_00/xData/hil099/run_0048_08-03-2023_01h08m57s/needleRU_i48_0048_0007.caendat
run data =

RU =  8.69 MB/s

LF =   3.79 MB/s

Eagle Rated ch4: around 2.3 kHz

plunger: (2:48)

plunger run = 514

actual distance =  382.7 um

supposed distance = 382.7 um

micrometer =   383.5 um

position =  149.8 um

voltage =  2.144 V

Beam dump =  1.5 nA

Collimater=  0.5 nA

Count rates are still a bit high (~2.6kHz for EAGLE det4). Ge spectra looks fine compared to earlier ones.

From 13:00 the rate of the Ge [the chanel 4] is a bit higher (~2.15 kHz). And also the rate of other detectors.

the rates of detectors are still a bit higher

41_ge_single_theta 101,117,143 looks ok. No peakdeformation of 511, other gammas FWHM around half of that of511 - ok

ch4 in total rate EAGLE_0 arouns 2.1 kHz - ok

planger tollerace limits (green and blue horizontal markers) set far of the current distance, intantionally?

ch4 in total rate EGALE_) reached 2.4 kHz, beam intensity has been reduced to fit the required 2kHz.

Again beam intensity gradually increased reaching 2.4 kHz ontotal rate EAGLE_0 ch4.  Beam intensity reduction requested. 1.8 kHz on ch4 after reduction.

Again beam intensity to high. Reduced to 2 kHz on ch4 GE

Beam stable, counting rate within limits, plunger distance within the given tollerance, gamma spectra ok, everything looks good but....

(yes there must be some "but"), refreshing of EAGLE_array_monitor.mat and NEDA_array_monitor.mat are out of sync. Mostly pure red colour is dysplayed. Not very usefull and (I suppose) missleading information.

Plunger run files for later to calculate error in the distance

At about 12:00, 13/03/2023 (about  17 hours after the beam was stopped), a measurement of activity of the beam line was performed using  FH 40G-L10 meter.

Radioctivity run 65 stopped before the measurement, radioactivity run  66 started after the measurement

Background level 120 ns/h

Target, stopper, the forward half of the target chamber - dismounted.

Approximate distance from the target position (upstream), approximate activity

10 cm    500 ns/h

25 cm    420 ns/h

35          350 ns/h

40          350 ns/h

50          200 ns/h

75          170 ns/h

run 66 started, radiocativity (background)

Attached are the lists of files copied to the two 4 TB Bahadir's disks.

16/03/2023

Plunger chamber closed, some dummy target and stopper probably inside

run 72    eagle closed

run 73    right half of EAGLE completely opened

Three screenshots are attached:

Run 72  EAGLE closed

1)  Three rings.  There is significantly more 511 in ring 143 than in 117, 101

2) 5 detectors of ring 143. They all look similar to each other.

Run 73  right half of EAGLE opened

3) 5 detectors of ring 143.  The 3 detectors in the opened half hardly see 511 keV, the other 2 do.

Check with Colibri and a gamma scintillator probe ws done: largest activity is visible close to the target chamber, in the region starting at the edge of the chamber, end ending about 6 cm upstream.

About 80 gamma counts/s are seen there. The count rate decreases further upstream.

Background rate:  20 to 30 counts/s, 25 counts/s in Sala Fizykow.

Radioactivity line seen in the spectra,  with the same behaviour as 511:   743.5,  936 keV, 1434 keV.  These are lines from 52Cr, fed by beta+ decay of 52Mn.

Confirmed by Michain gamma-gamma.

52Mn can be produced in the a2pn channel in  the reaction 32S+27Al